The use of spinal stabilization/fixation devices to align or position specific vertebra or a region of the spine is well established. Typically such devices utilize a spinal fixation element, comprised of a relatively rigid member such as a plate, board or rod that is used as a coupler between adjacent vertebrae. Such a spinal fixation element can effect a rigid positioning of adjacent vertebrae when attached (e.g. to the pedicle portion of the vertebra) using bone anchorage screws (e.g. pedicle screws). Once the coupled vertebrae are spatially fixed in position, procedures can be performed, healing can proceed or spinal fusion may take place.
Spinal fixation elements may be introduced posteriorly to stabilize the various vertebrae of the spine, for example, in conjunction with a kyphoplasty procedure wherein a void or cavity is made inside a vertebral body followed by filling with a bone substitute to form an “internal cast.” Some conventional devices for this purpose are designed to be attached directly to the posterior of the spine, but the generally invasive nature of a conventional posterior approach used to implant these devices poses drawbacks. One minimally invasive solution to the problem of the posterior approach involves making a longitudinal separation of the sacrospinalis group between the multifudus and longissimus utilizing the natural cleavage plane between these two muscles rather than detaching the paraspinal muscles from the posterior spinal elements. Problems stemming from the prior art solutions include a high degree of invasiveness resulting in muscle disruption and blood loss. The loss of the paraspinal muscle attachment sites, formation of scar tissue, and loss of muscle function may compromise the patient's final outcome. Additionally, the prior art solutions are time consuming and are difficult to remove.